The present invention relates to novel substituted diamine derivatives, pharmaceutical compositions containing them and intermediates used in their manufacture. More particularly, the compounds of the invention are motilin receptor antagonists useful for the treatment of associated conditions and disorders such as gastrointestinal reflux disorders, eating disorders leading to obesity and irritable bowel syndrome.
In mammals, the digestion of nutrients and the elimination of waste are controlled by the gastrointestinal system. Within this system, there are a number of natural peptides, ligands, enzymes, and receptors which play a vital role and are potential targets for drug discovery. Modifying the production of, or responses to these endogenous substances can have an effect upon the physiological responses such as diarrhea, nausea, and abdominal cramping. One example of an endogenous substance which affects the gastrointestinal system is motilin.
Motilin is a peptide of 22 amino acids which is produced in the gastrointestinal system of a number of species. Although the sequence of the peptide varies from species to species, there are a great deal of similarities. For example, human motilin and porcine motilin are identical; while motilin isolated from the dog and the rabbit differ by five and four amino acids respectively. Motilin induces smooth muscle contractions in the stomach tissue of dogs, rabbits, and humans as well as in the colon of rabbits. Apart from local gastrointestinal intestinal tissues, motilin and its receptors have been found in other areas. For example motilin has been found in circulating plasma, where a rise in the concentration of motilin has been associated with gastric effects which occur during fasting in dogs and humans. Itoh, Z. et al. Scand. J. Gastroenterol. 11:93-110, (1976); Vantrappen, G. et al. Dig. Dis Sci 24, 497-500 (1979). In addition, when motilin was intravenously administered to humans it was found to increase gastric emptying and gut hormone release. Christofides, N. D. et al. Gastroenterology 76:903-907, 1979.
Aside from motilin itself, there are other substances which are agonists of the motilin receptor and which elicit gastrointestinal emptying. One of those agents is the antibiotic erythromycin. Even though erythromycin is a useful drug, a great number of patients are affected by the drug""s gastrointestinal side effects. Studies have shown that erythromycin elicits biological responses that are comparable to motilin itself and therefore may be useful in the treatment of diseases such as chronic idiopathic intestinal pseudo-obstruction and gastroparesis. Weber, F. et al., The American Journal of Gastroenterology, 88:4, 485-90 (1993).
Although motilin and erythromycin are agonists of the motilin receptor, there is a need for antagonists of this receptor as well. The nausea, abdominal cramping, and diarrhea which are associated with motilin agonists are unwelcome physiological events. The increased gut motility induced by motilin has been implicated in diseases such as Irritable Bowel Syndrome and esophageal reflux. Therefore researchers have been searching for motilin antagonists.
One such antagonist is OHM-11526. This is a peptide derived from porcine motilin which competes with both motilin and erythromycin for the motilin receptor in a number of species, including rabbits and humans. In addition, this peptide is an antagonist of the contractile smooth muscle response to both erythromycin and motilin in an in vitro rabbit model. Depoortere, I. et al., European Journal of Pharmacology, 286, 241-47, (1995). Although this substance is potent in that model (IC50 1.0 nM) it is a peptide and as such offers little hope as an oral drug since it is susceptible to the enzymes of the digestive tract. Zen Itoh, Motilin, xvi (1990). Therefore it is desirable to find other non-peptidic agents which act as motilin antagonists. The compounds of this invention are such agents.
The compounds of this invention are non-peptidyl motilin antagonists with potencies and activities comparable to known peptidyl motilin antagonists. These compounds compete with motilin and erythromycin for the motilin receptor site in vitro. In addition, these compounds suppress smooth muscle contractions induced by motilin and erythromycin with activities and potencies comparable to OHM 11526 in an in vitro model.
The present invention is directed to compounds of the formula (I): 
wherein
R1 is selected from the group consisting of hydrogen, aryl, aralkyl, heterocyclyl, diarylalkyl, heterocyclyl-alkyl, and lower alkyl; wherein the alkyl, aryl or heterocyclyl moieties in the foregoing groups may be substituted with one or more substituents independently selected from halogen, hydroxy, nitro, carboxy, cyano, amino, dialkylamino, lower alkoxy, lower alkyl, tri-halomethyl, alkylamino, carboxy and alkoxycarbonyl;
R2 is selected from the group consisting of aryl, aralkyl, cycloalkyl, cycloalkyl-alkyl, heterocyclyl, heterocyclyl-alkyl, diarylalkyl, aminoalkyl, tri-halomethyl, arylamino and lower alkyl; wherein the alkyl, aryl, heterocyclyl-alkyl, heterocyclyl, or amino moieties in the foregoing groups may be substituted with one or more substituents independently selected from halogen, hydroxy, nitro, cyano, amino, dialkylamino, lower alkoxy, lower alkyl, tri-halomethyl, alkylamino, phenyl, carboxy, carboxyalkyl and alkoxycarbonyl;
X1, X2, X3 and X4 are independently absent or selected from the group consisting of CO and SO2; provided that at least one of X1 or X2 and at least one of X3 or X4 is CO or SO2;
alternatively R1, R2 and X1 can be taken together (with the amine nitrogen) to form a monocyclic or fused bicyclic or tricyclic secondary amine ring structure; wherein the monocyclic or fused bicyclic or tricyclic secondary amine ring structure may be optionally substituted with one or more substituents independently selected from halogen, oxo, nitro, cyano, amino, alkylamino, dialkylamino, trialkylamino, lower alkoxy, lower alkyl, tri-halomethyl, carboxy, acetyloxy, alkoxycarbonyl, aryl, aralkyl andr heterocyclyl;
A is selected from the group consisting of lower alkyl, lower alkenyl, cycloalkyl, cycloalkyl-alkyl, alkyl-cycloalkyl, cycloalkenyl, cycloalkenyl-alkyl, alkyl-cycloalkenyl, alkyl-cycloalkyl-alkyl; alkyl-aryl-alkyl, alkyl-aryl, aryl-alkyl and phenyl; where, in each case, the A group may optionally be substituted with one or more substituents selected from R7;
where R7 is selected from alkyl, tri-halomethyl, cycloalkyl, aryl, aralkyl, heterocyclyl, heterocyclyl-alkyl, diarylalkyl, aminoalkyl, or arylamino; wherein the alkyl, aryl, heterocyclyl-alkyl, heterocyclyl, or amino moieties in the foregoing groups may be substituted with one or more substituents independently selected from halogen, hydroxy, nitro, cyano, amino, dialkylamino, lower alkoxy, lower alkyl, tri-halomethyl, alkylamino, phenyl, carboxy and alkoxycarbonyl;
provided that A is not -1,3-cyclopentyl-1-ene-alkyl;
R3 is selected from the group consisting of hydrogen, aryl, heterocyclyl, aralkyl, diarylalkyl, heterocyclo-alkyl, tri-halomethyl, alkylamino, arylamino and lower alkyl; wherein the aryl, heterocyclyl, aralkyl, diarylalkyl, heterocyclyl-alkyl, alkylamino, arylamino or lower alkyl group may be substituted with one or more substituents independently selected from halogen, nitro, cyano, amino, dialkylamino, lower alkoxy, lower alkyl, tri-halomethyl, carboxy and alkoxycarbonyl;
Y is selected from the group consisting of xe2x80x94Oxe2x80x94, xe2x80x94NHxe2x80x94, xe2x80x94Sxe2x80x94 and xe2x80x94SO2xe2x80x94;
n is an integer from 0 to 5;
R4 is selected from the group consisting of hydrogen, amino, alkylamino, dialkylamino, N-alkyl-N-aralkyl-amino, trialkylamino, dialkylaminoalkoxyalkyl, heterocyclyl, heterocyclyl-alkyl, oxo-substituted heterocyclyl and lower alkyl-substituted heterocyclyl;
R5 is selected from the group consisting of hydrogen, halogen, nitro, cyano, amino, alkylamino, dialkylamino, trialkylamino, lower alkoxy, lower alkyl, tri-halomethyl, carboxy and alkoxycarbonyl;
and the pharmaceutically acceptable salts, esters and pro-drug forms thereof.
Relative to the above generic description, certain compounds of the general formula are preferred. 
where p and t are integers from 1-6. More preferably, R4 is selected from the group consisting of hydrogen, 4-morpholinyl, 1-pyrrolidinyl, 2-oxo-pyrrolidin-1-yl, 2-(1-methylpyrrolidinyl), 1-piperazinyl, 1-piperidinyl, di(methyl)aminoethyloxyethyl, N-methyl-N-benzyl-amino, di(methyl)amino and diethylamino. More preferably still, R4 is selected from the group consisting of hydrogen, 4-morpholinyl, 1-pyrrolidinyl, 1-piperazinyl, 1-piperidinyl, di(methyl)amino and di(ethyl)amino. More preferably still, R4 is selected from the group consisting of hydrogen, 4-morpholinyl, 1-pyrrolidinyl, 1-piperidinyl and di(methyl)amino. Most preferably, R4 is selected from the group consisting of hydrogen, 4-morpholinyl, 1-pyrrolidinyl and 1-piperidinyl;
Preferably R5 is selected from the group consisting of hydrogen and lower alkyl. More preferably R5 is selected from the group consisting of hydrogen and methyl.
In a preferred embodiment of the present invention are those compounds of general formula (I) wherein:
R1 is selected from the group consisting of hydrogen, aralkyl, heterocyclyl and heterocyclyl-alkyl; where the aralkyl, heterocyclyl or heterocyclyl-alkyl may be substituted with one or more substituents independently selected from halogen, lower alkyl, lower alkoxy, tri-halomethyl, hydroxy or nitro;
R2 is selected from the group consisting of alkyl, tri-halomethyl, aryl, aralkyl, arylamino, biphenyl, cycloalkyl, cycloalkyl-alkyl, heterocyclyl and heterocyclyl-alkyl; where the aryl, aralkyl or heterocyclyl group may be substituted with one or more substituents independently selected from halogen, lower alkoxy, nitro, carboxy, carboxyalkyl, hydroxy, phenyl, diphenylmethyl, tri-halomethyl or trihaloalkylacetyl;
X1, X2, X3 and X4 are independently absent or selected from the group consisting of CO and SO2; such that at least one of X1 or X2 and at least one of X3 or X4 is CO or SO2;
A is selected from the group consisting of lower alkyl, alkyl-cycloalkyl, cycloalkyl-alkyl, -cycloalkyl, -cycloalkenyl-, cycloalkenyl-alkyl- and -aryl-alkyl-; where the alkyl moiety in the foregoing groups may be substituted with one or more substituents independently selected from aralkyl or cycloalkyl;
provided that A is not -1,3-cyclopentyl-1-ene-alkyl;
R3 is selected from the group consisting of hydrogen, aryl, aralkyl and arylamino; where the aryl or aralkyl group may be substituted with one or more substituents independently selected from halogen, lower alkyl, lower alkoxy or tri-halomethyl;
Y is xe2x80x94Oxe2x80x94;
n is an integer from 0 to 3;
R4 is selected from the group consisting of hydrogen, heterocyclyl, oxo-substituted heterocyclyl, lower alkyl-substituted heterocyclyl, di(lower alkyl)amino, N-lower alkyl-N-aralkyl-amino and di(lower alkyl)amino alkoxy alkyl;
R5 is selected from the group consisting of hydrogen and lower alkyl;
and the pharmaceutically acceptable salts, esters and pro-drug forms thereof.
In a preferred embodiment are compounds of the general formula (I) wherein:
R1 is selected from the group consisting of hydrogen, phenyl (C1-C6) alkyl-, naphthyl(C1-6)alkyl and heterocyclyl (C1-C6)alkyl- where the heterocyclyl group is selected from pyridyl and where the phenyl, naphthyl or heterocyclyl moiety is optionally substituted with one to three substituents selected from halogen, lower alkyl, lower alkoxy, tri-halomethyl, hydroxy and nitro;
R2 is selected from the group consisting of (C1-C6)branched or unbranched alkyl, phenyl, phenyl(C1-C6)alkyl-, tri-halomethyl, phenylamino-, biphenyl, diphenyl(C1-C6)alkyl-, C5-8cycloalkyl, C5-8cycloalkyl-alkyl,heterocyclyl and heterocyclyl(C1-C6)alkyl- wherein the heterocyclyl moiety is selected from naphthyl, furyl, pyridyl, pyrrolidinyl and thienyl and wherein the phenyl or heterocyclyl group may be substituted with one to four substitutuents selected from halogen, lower alkoxy, nitro, carboxy, carboxy(C1-4)alkyl, hydroxy, phenyl, diphenylmethyl, trihalomethyl and trihaloalkylacetyl;
X1, X2, X3 and X4 are independently absent or selected from the group consisting of CO and SO2; such that at least one of X1 or X2 and at least one of X3 or X4 is CO or SO2;
A is selected from the group consisting of lower alkyl, loweralkyl-cycloalkyl, cycloalkyl-loweralkyl, -cycloalkyl, -cycloalkenyl-, cycloalkenyl-loweralkyl- and -phenyl-loweralkyl- and -benzyl-loweralkyl, provided that A is not -1,3-cyclopentyl-1-ene-alkyl;
R3 is selected from the group consisting of hydrogen, phenyl, benzyl and phenylamino-; where the phenyl or benzyl moieties may be substituted with one to three substituents selected from halogen, lower alkyl, lower alkoxy and trihalomethyl;
Y is xe2x80x94Oxe2x80x94;
n is an integer from 0 to 3;
R4 is selected from the group consisting of hydrogen, heterocyclyl, oxo substituted heterocyclyl, lower alkyl-substituted heterocyclyl, di(loweralkyl) amino, N-lower alkyl-N-aralkyl-amino and a moiety of the formula: 
where p and t are integers from 1-6;
R5 is selected from hydrogen and lower alkyl;
and the pharmaceutically acceptable salts esters and pro-drug forms thereof.
In a more preferred embodiment of the present invention are compounds of the general formula (I) wherein
R1 is selected from the group consisting of hydrogen, benzyl, 2-(phenyl)ethyl, 4-methylbenzyl, 3-methoxybenzyl, 3-nitrobenzyl, 3-chlorobenzyl, 3-fluorobenzyl, 4-chlorobenzyl, 2,3-dichlorobenzyl, 3,4-dichlorobenzyl, 3,5-dichlorobenzyl, 3,4-difluorobenzyl, 3-trifluoromethylbenzyl, 1-naphthyl-methyl, 2-pyridyl-methyl and 4-(1-hydroxy)pyridyl;
R2 is selected from the group consisting of methyl, ethyl, t-butyl, 2,2-dimethylpropyl, benzyl, 2-(phenyl)ethyl, 3-(phenyl)propyl, 1-(phenyl)propyl, 3-carboxy-n-propyl, 3-carboxy-3-methyl-n-butyl, 2,2-dimethyl-3-carboxy-n-propyl, trichloromethyl, trifluoromethyl, 2-naphthyl, phenylamino, 3-methoxyphenyl, 3-hydroxyphenyl, 4-fluorobenzyl, 3-carboxybenzyl, 3-methoxybenzyl, 4-methoxybenzyl, 3,4-dimethoxybenzyl, 2-(4-methoxyphenyl)ethyl, 4-fluorophenyl, 2-(4-chlorophenyl)ethyl, 3-nitrophenyl, 3,5-di(trifluoromethyl)phenyl, 3,3,3-trifluoropropan-2-oyl, diphenylmethyl, 4-biphenyl, 3-carboxymethyl-1,2,2-trimethyl-cyclopentyl, cyclopentylethyl, (1-carboxymethyl-cyclopentyl)-methyl, 2-furyl, 2-pyridyl-(2-ethyl), 1-pyrrolidinyl-(2-ethyl), 2-theinylmethyl and 2-thienylethyl;
X1, X2, X3 and X4 are independently absent or selected from the group consisting of CO and SO2; such that one of X1 or X2 and one of X3 or X4 is CO or SO2;
A is selected from the group consisting of 1,2-ethyl, 1,3-propyl, 1,4-butyl, 2-methyl-1,3-propyl, 1,1,-dimethyl-(1,3-propyl), 2-cyclopentyl-1,3-n-propyl, 1S,3R-cyclopentyl-methyl, 1,2-cyclopent-1-enyl, 1,4-cyclopentyl-2-ene-methyl, methyl-1,3-cyclohexyl, 1,2-cyclohexyl-methyl-, 1,3-cyclohexyl-methyl-, 1S,3R-cyclohexyl-methyl-, 1R,3S-cyclohexyl-methyl, 1,4-cyclohexyl-methyl-, 1,2-cyclohex-4-enyl, 1,3-phenyl-methyl and 1-benzyl-methyl-;
R3 is selected from the group consisting of hydrogen, phenylamino, 4-methylphenyl, 4-fluorophenyl, 2-fluorobenzyl, 3-fluorobenzyl, 4-fluorobenzyl, 4-chlorobenzyl, 4-methoxybenzyl and 4-trifluoromethylbenzyl;
Y is selected from the group consisting of -3-Oxe2x80x94 and -4-Oxe2x80x94;
n is an integer selected from 0, 2 or 3;
R4 is selected from the group consisting of hydrogen, 4-morpholinyl, 1-pyrrolidinyl, 2-oxo-pyrrolidin-1-yl, 2-(1-methylpyrrolidinyl), 1-piperazinyl, 1piperidinyl, di(methyl)aminoethyloxyethyl, N-methyl-N-benzyl-amino, di(methyl)amino and diethylamino;
R5 is selected from the group consisting of hydrogen, 2-methyl and 6-methyl;
and the pharmaceutically acceptable salts, esters and pro-drug forms thereof.
In another preferred embodiment of the present invention are compounds of the formula (I) wherein R1, R2 and X1 are taken together (with the amine nitrogen) to form an optionally substituted, monocyclic or fused bicyclic or tricyclic secondary amine ring structure selected from the group consisting of 1-phenyl-1,2,3,4-tetrahydroisoquinolinyl, 4-[(4-chlorophenyl)phenylmethyl]piperazin-1-yl, 2-[1-benzyl-6-methoxy-1,2,3,4-tetrahydro]naphthyl, isoindole-1,3-dione, 5-t-butyl-isoindole-1,3-dione, 5-fluoro-isoindole-1,3-dione, 5-methyl-isoindole-1,3-dione, 5,6-dichloro-isoindole-1,3-dione, 4,7-dichloro-isoindole-1,3-dione, 5-bromo-isoindole-1,3-dione, 5-acetyloxy-isoindole-1,3-dione, benzo[e]isoindole-1,3-dione, 8-fluorobenzo[e]isoindole- 1,3-dione, 4,4-dimethyl-piperidine-2,6-dione, 3-aza-bicyclo[3.1.0]hexane-2,6-dione and 8-aza-spiro[4.5]decane-7,9-dione; and the pharmaceutically acceptable salts, esters and pro-drug forms thereof.
In a particularly preferred embodiment R1, R2 and X1 are taken together (with the amine nitrogen) to form 1-phenyl-1,2,3,4-tetrahydroisquinolinyl, X2 is C(O), A is 1,3-propyl, X3 is C(O), R3 is 4-fluorobenzyl, Y is 3-Oxe2x80x94, n is 2 and R4 is 4-morpholinyl.
In another preferred embodiment R1, R2 and X1 are taken together (with the amine nitrogen) to form 4-[(4-chlorophenyl)phenylmethyl]piperazin-1-yl, X2 is C(O), A is 1,3-n-propyl, X3 is absent, R3 is 4-fluorophenyl, X4 is C(O), Y is 3-Oxe2x80x94, n is 2 and R4 is 4-morpholinyl.
In still another preferred embodiment, R1, R2 and X1 are taken together (with the amine nitrogen) to form 2-[1-benzyl-6-methoxy-1,2,3,4-tetrahydro]-naphthyl, X2 is C(O), A is 1,3-n-propyl, X3 is absent, R3 is 4-fluorophenyl, X4 is C(O), Y is 3-Oxe2x80x94, n is 2 and R4 is 4-morpholinyl.
In a class of the invention are compounds of the formula (I) wherein
R1 is selected from the group consisting of benzyl, 2-(phenyl)ethyl, 3-nitrobenzyl, 3-chlorobenzyl, 3,4-dichlorobenzyl, 3,4-difluorobenzyl, 3,5-dichlorobenzyl, 3-trifluoromethylbenzyl and 2-pyridyl-methyl;
R2 is selected from the group consisting of t-butyl, 2-(phenyl)ethyl, trichloromethyl, 3-carboxybenzyl, 3-methoxybenzyl, 2-(4-methoxyphenyl)ethyl, 2-(4-chlorophenyl)ethyl, diphenylmethyl, 2-(2-pyridyl)ethyl, 2-(1-pyrrolidinyl)ethyl and 2-(2-thienyl)ethyl;
X1, X2, X3 and X4 are independently absent or CO; such that one of X1 or X2 and one of X3 or X4 is CO;
A is selected from the group consisting of 1,2-ethyl, 1,3-propyl, 2-methyl-1,3-propyl, 1,1,-dimethyl-(1,3-propyl), 2-cyclopentyl-1,3-n-propyl, 1S,3R-cyclopentyl-methyl, 1,3-cyclohexyl-methyl, 1S,3R-cyclohexyl-methyl- and 1R,3S-cyclohexyl-methyl-;
R3 is selected from the group consisting of phenylamino, 4-fluorophenyl, 3-fluorobenzyl, 2-fluorobenzyl, 4-fluorobenzyl, 4-chlorobenzyl, 4-methoxybenzyl and 4-trifluoromethylbenzyl;
Y is selected from the group consisting of -3-Oxe2x80x94 and -4-Oxe2x80x94;
n is an integer selected from 2 or 3;
R4 is selected from the group consisting of hydrogen, 4-morpholinyl, 1-pyrrolidinyl, 1-piperazinyl, 1-piperidinyl, di(methyl)amino and di(ethyl)amino;
R5 is selected from the group consisting of hydrogen, 2-methyl and 6-methyl;
and the pharmaceutically acceptable salts, esters and pro-drug forms thereof.
In another class of the invention are compounds of the formula (I) wherein
R1 is selected from the group consisting of benzyl, 2-(phenyl)ethyl, 3-nitrobenzyl, 3-chlorobenzyl, 3,4-dichlorobenzyl, 3,4-difluorobenzyl, 3,5-dichlorobenzyl and 3-trifluoromethylbenzyl;
R2 is selected from the group consisting of t-butyl, 2-(phenyl)ethyl, trichloromethyl, 3-carboxybenzyl, 3-methoxybenzyl, 2-(2-pyridyl)ethyl and 2-(2-thienyl)ethyl;
X1, X2, X3 and X4 are independently absent or CO; such that one of X1 or X2 and one of X3 or X4 is CO;
A is selected from the group consisting of 1,3-propyl, 1S,3R-cyclopentyl-methyl, 1,3-cyclohexyl-methyl-, 1S,3R-cyclohexyl-methyl- and 1R,3S-cyclohexyl-methyl-;
R3 is selected from the group consisting of phenylamino, 4-fluorophenyl, 3-fluorobenzyl and 4-fluorobenzyl;
Y is-3-Oxe2x80x94;
n is 2;
R4 is selected from the group consisting of hydrogen, 4-morpholinyl, 1-pyrrolidinyl, 1-piperidinyl and di(methyl)amino;
R5 is selected from the group consisting of hydrogen, 2-methyl and 6-methyl;
and the pharmaceutically acceptable salts, esters and pro-drug forms thereof.
Particularly preferred are compounds of the formula (I) wherein
R1 is selected from the group consisting of benzyl, 3-nitrobenzyl, 3-chlorobenzyl, 3,4-dichlorobenzyl, 3,4-difluorobenzyl and 3-trifluoromethylbenzyl;
R2 is selected from the group consisting of t-butyl, 2-(phenyl)ethyl, trichloromethyl, 2-(2-pyridyl)ethyl and 2-(2-thienyl)ethyl;
X1, X2, X3 and X4 are independently absent or CO; such that one of X1 or X2 and one of X3 or X4 is CO;
A is selected from the group consisting of 1,3-propyl, 1S,3R-cyclopentyl-methyl, 1,3-cyclohexyl-methyl-, 1S,3R-cyclohexyl-methyl- and 1R,3S-cyclohexyl-methyl-;
R3 is selected from the group consisting of phenylamino, 4-fluorophenyl, 3-fluorobenzyl and 4-fluorobenzyl;
Y is -3-Oxe2x80x94;
n is 2;
R4 is selected from the group consisting of hydrogen, 4-morpholinyl, 1-pyrrolidinyl and 1-piperidinyl;
R5 is selected from the group consisting of hydrogen and 2-methyl;
and the pharmaceutically acceptable salts, esters and pro-drug forms thereof.
In still another particularly preferred embodiment of the present invention are compounds of the formula (I) wherein R1 is 3-chlorobenzyl, R2 is trichloromethyl, X1 is CO, X2 is absent, X3 is absent, X4 is CO, A is 1S,3R-cyclohexyl-methyl-, R3 is 4-fluorophenyl, Y is -3-Oxe2x80x94, n is 2, R4 is 1-piperidinyl, R5 is hydrogen and the pharmaceutically acceptable salts, esters and pro-drug forms thereof.
In still another particularly preferred embodiment of the present invention are compounds of the formula (I) wherein R1 is 3-chlorobenzyl, R2 is trichloromethyl, X1 is CO, X2 is absent, X3 is absent, X4 is CO, A is 1R,3S-cyclohexyl-methyl-, R3 is 4-fluorophenyl, Y is -3-Oxe2x80x94, n is 2, R4 is 1-piperidinyl, R5 is hydrogen and the pharmaceutically acceptable salts, esters and pro-drug forms thereof.
Listed in Tables 1-16 are specific compounds of the present invention.
Particularly preferred intermediates in the preparation of compounds of formula (I) are listed Table 17 below.
Illustrative of the invention is a pharmaceutical composition comprising a pharmaceutically acceptable carrier and any of the compounds described above. Illustrating the invention is a pharmaceutical composition made by mixing any of the compounds described above and a pharmaceutically acceptable carrier. A further illustration of the invention is a process for making a pharmaceutical composition comprising mixing any of the compounds described above and a pharmaceutically acceptable carrier.
Included in the invention is the use of any of the compounds described above for the preparation of a medicament for treating a disorder mediated by the motilin receptor, in a subject in need thereof.
Also included in the invention is the use of any of the compounds described above for the preparation of a medicament for treating a condition selected from gastrointestinal reflux disorders, eating disorders leading to obesity and irritable bowel syndrome in a subject in need thereof.
Exemplifying the invention are methods of treating a disorder mediated by the motilin receptor, in a subject in need thereof, comprising administering to the subject a therapeutically effective amount of any of the compounds or pharmaceutical compositions described above.
An example of the invention is a method for treating a condition selected from gastrointestinal reflux disorders, eating disorders leading to obesity and irritable bowel syndrome in a subject in need thereof, comprising administering to the subject an effective amount of any of the compounds or pharmaceutical compositions described above.
Another example of the invention is the use of any of the compounds described above in the preparation of a medicament for: (a) treating gastrointestinal reflux disorders, (b) treating irritable bowel syndrome, (c) treating eating disorders leading to obesity, in a subject in need thereof.
Listed below are definitions of various terms used to describe this invention. These definitions apply to the terms as they are used throughout this specification, unless otherwise limited in specific instances, either individually or as part of a larger group.
The term xe2x80x9chalogenxe2x80x9d or xe2x80x9chaloxe2x80x9d refers to fluorine, chlorine, bromine and iodine.
The term xe2x80x9calkylxe2x80x9d, unless otherwise specified, refers to straight or branched chain unsubstituted hydrocarbon groups of 1 to 20 carbon atoms, preferably 1 to 8 carbon atoms. The expression xe2x80x9clower alkylxe2x80x9d refers to straight or branched chain unsubstituted alkyl groups of 1 to 6 carbon atoms. For example, alkyl radicals include, methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, t-butyl, n-pentyl, 3-methylbutyl, 2-pentyl, 2-methylpropyl, 2-methylbutyl, 3,3-dimethylpropyl, neo-pentyl, n-hexyl, 2-hexyl and 2-methylpentyl. Similarly, the term xe2x80x9calkenylxe2x80x9d, unless otherwise specified, refers to straight or branched chain alkene groups of 2 to 10 carbon atoms. The term xe2x80x9clower alkenylxe2x80x9d refers to straight or branched chain alkene groups of 2 to 6 carbon atoms.
The term xe2x80x9csubstituted alkylxe2x80x9d, unless otherwise specified, refers to an alkyl group substituted by, for example, one to four substituents, such as, halo, trifluoromethyl, trifluoromethoxy, hydroxy, alkoxy, cycloalkyoxy, heterocyclyloxy, oxo, alkanoyl, aryloxy, alkanoyloxy, amino, alkylamino, arylamino, aralkylamino, cycloalkylamino, heterocycloamino, disubstituted amines in which the amino substituents are independently selected from alkyl, aryl or aralkyl, alkanoylamine, aroylamino, aralkanoylamino, substituted alkanoylamino, substituted arylamino, substituted aralkanoylamino, thiol, alkylthio, arylthio, aralkylthio, cycloalkylthio, heterocyclothio, alkylthiono, arylthiono, aralkylthiono, alkylsulfonyl, arylsulfonyl, aralkylsulfonyl, sulfonamido (e.g. SO2NH2), substituted sulfonamido, nitro, cyano, carboxy, carbamyl (e.g. CONH2) substituted carbamyl (e.g. CONH alkyl, CONH aryl, CONH aralkyl or cases where there are two substituents on the nitrogen selected from alkyl, aryl or aralkyl), alkoxycarbonyl, aryl, substituted aryl, guanidino and heterocyclos, such as indolyl, imidazolyl, furyl, thienyl, thiazolyl, pyrrolidyl, pyridyl, pyrimidyl and the like.
The term xe2x80x9ccycloalkylxe2x80x9d, unless otherwise specified, refers to saturated unsubstituted cyclic hydrocarbon ring systems, preferably containing 1 to 3 rings and 3 to 8 carbon atoms per ring. For example, cycloalkyl radicals include cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, and the like. Similarly, the term xe2x80x9ccycloalkenylxe2x80x9d refers to partially unsaturated, unsubstituted cyclic hydrocarbon groups of 3 to 20 carbon atoms, preferably 3 to 8 carbon atoms. Suitable examples of cycloalkenyl groups include cyclobutenyl, cyclopentenyl, cyclohexenyl, cyclooctyl, cyclodecyl, cyclododecyl, adamantyl, and the like.
The term xe2x80x9calkoxyxe2x80x9d, unless otherwise specified, refers to oxygen ether radical of the above described straight or branched chain alkyl groups. The expression xe2x80x9clower alkoxyxe2x80x9d refers to unsubstituted alkoxy groups of 1 to 6 carbon atoms. Suitable examples of alkoxy groups include methoxy, ethoxy, n-propoxy, sec-butoxy, t-butoxy, n-hexyloxy and the like.
The term xe2x80x9carylxe2x80x9d, unless otherwise specified, refers to monocyclic or bicyclic aromatic hydrocarbon groups having 6 to 12 carbon atoms in the ring portion, such as phenyl, naphthyl, biphenyl and diphenyl, each of which may be optionally substituted.
The term xe2x80x9caralkylxe2x80x9d, unless otherwise specified, refers to an aryl group bonded directly through an alkyl group, such as benzyl, 2-(phenyl)ethyl, 3-(phenyl)propyl, naphthyl-methyl and the like.
The term xe2x80x9csubstituted arylxe2x80x9d refers to an aryl group substituted by, for example, one to five substituents such as alkyl; substituted alkyl, halo, trifluoromethoxy, trifluoromethyl, hydroxy, alkoxy, cycloalkyloxy, heterocyclooxy, alkanoyl, alkanoyloxy, amino, alkylamino, aralkylamino, cycloalkylamino, heterocycloamino, dialkylamino, alkanoylamino, thiol, alkylthio, cycloalkylthio, heterocyclothio, ureido nitro, cyano, carboxy, carboxyalkyl, carbamyl, alkoxycarbonyl, alkylthiono, arylthiono, alkysulfonyl, sulfonamido, aryloxy and the like.
The term xe2x80x9cdiarylalkylxe2x80x9d, unless otherwise specified, refers to an alkyl group substituted with two independently selected aryl groups. Suitable examples include diphenylmethyl, 1,1-diphenylethyl, and the like.
The term xe2x80x9cheteroatomxe2x80x9d shall include oxygen, sulfur and nitrogen.
The terms xe2x80x9cheterocyclylxe2x80x9d, xe2x80x9cheterocyclicxe2x80x9d and xe2x80x9cheterocycloxe2x80x9d, unless otherwise specified, refer to a saturated, unsaturated, partially unsaturated, aromatic, partially aromatic or non-aromatic cyclic group. Such a group, for example, can be a 4 to 7 membered monocyclic or a 7 to 11 bicyclic ring system which contains at least one heteroatom in at least one carbon atom containing ring. Each ring of the heterocyclic group containing a heteroatom may have 1, 2, 3 or 4 heteroatoms selected from nitrogen atoms, oxygen atoms and sulfur atoms, where the nitrogen and sulfur heteroatoms may also optionally be oxidized and where the nitrogen heteroatoms may also optionally be quaternized. The heterocyclic group may be attached at any heteroatom or carbon atom.
Exemplary monocyclic heterocyclic groups include pyrrolidinyl, pyrrolyl, indolyl, pyrazolyl, oxetanyl, pyrazolinyl, imidazolyl, imidazolinyl, imidazolidinyl, oxazolyl, oxazolidinyl, isoxazolinyl, isoxazolyl, thiazolyl, thiadiazolyl, thiazolidinyl, isothiazolyl, isothiazolidinyl, furyl, tetrahydrofuryl, thienyl, oxadiazolyl, piperidinyl, piperazinyl, 2-oxopiperazinyl, 2-oxopiperidinyl, 2-oxopyrrolidinyl, 2-oxazepinyl, azepinyl, 4-piperidonyl, pyridyl, N-oxo-pyridyl, pyrazinyl, pyrimidinyl, pyridazinyl, tetrahydropryanyl, tetrahydrothiopyranyl, tetrahydrothiopyranyl sulfone, morpholinyl, thiomorpholinyl, thiomorpholinyl sulfoxide, thiomorpholinyl sulfone, 1,3-dioxolane, tetrahydro-1,1-dioxothienyl, dioxanyl, isothiazolidinyl, thietanyl, thiiranyl, triazinyl, triazolyl, tetrazolyl and the like.
Exemplary bicyclic heterocyclic groups include benzothiazolyl, benzoxazolyl, benzothienyl, quinuclidinyl, quinolinyl, quinolinyl-N-oxide, tetrahydroisoquinolinyl, isoquinolinyl, benzimidazolyl, benzopyranyl, indolizinyl, benzofuryl, chromonyl, coumarinyl, cinnolinyl, quinoxalinyl, indazolyl, pyrrolopyridyl, furopyridinyl (such as furo[2,3-c]pyridinyl, furo[3,1-b]pyridinyl, or furo[2,3-b]pyridinyl), dihydroisoindolyl, dihydroquinazolinyl (such as 3,4-dihydro-4-oxo-quinazolinyl), benzisothiazolyl, benzisoxazolyl, benzodiazinyl, benzofurazanyl, benzothiopyranyl, benzotriazolyl, benzpyrazolyl, dihydrobenzofuryl, dihydrobenzothienyl, dihydrobenzothiopyranyl, dihydrobenzothiopyranyl sulfone, dihydrobenzopyranyl, indolinyl, isochromanyl, isoindolinyl, naphthyridinyl, phthalazinyl, piperonyl, purinyl, pyridopyridyl, quinazolinyl, tetrahydroquinolinyl, thienofuryl, thienopyridyl, thienothienyl, and the like.
The term xe2x80x9cmonocyclic or fused bicyclic or tricyclic secondary amine ring structurexe2x80x9d shall mean any 4 to 8 monocyclic or 7 to 11 fused bicyclic or 13 to 14 tricyclic ring structure; wherein the ring structure is saturated, partially unsaturated or benzo-fuzed; wherein the ring structure contains at least one nitrogen atom through which the ring structure is bound directly to the other portions of the compound; and wherein the ring structure may optionally containing one to three additional heteroatoms selected from nitrogen, oxygen or sulfur.
Suitable examples include 1,2,3,4-tetrahydroisoquinolinyl, 1-piperazinyl, 1,2,3,4-tetrahydronaphthyl, isoindolyl, benzo[e]isoindolyl, 8-aza-spiro[4.5]decane, 3-aza-bicyclo[3.1.o]hexane, and the like.
The monocylic, bicyclic or tricyclic secondary amine ring structure may optionally be substituted with one to five substituents independently selected from alkyl, substituted alkyl, halo, trifluoromethoxy, trifluoromethyl, hydroxy, alkoxy, cycloalkyloxy, heterocyclooxy, alkanoyl, alkanoyloxy, amino, alkylamino, aralkylamino, cycloalkylamino, heterocycloamino, dialkylamino, alkanoylamino, thiol, alkylthio, cycloalkylthio, heterocyclothio, ureido nitro, cyano, oxo, carboxy, carboxyalkyl, carbamyl, alkoxycarbonyl, alkylthiono, arylthiono, alkysulfonyl, sulfonamido, aryloxy, aryl, aralkyl, heterocyclyl, and the like.
The term xe2x80x9ctri-halomethylxe2x80x9d refers to trichloromethyl, trifluoromethyl, tribromomethyl and triiodomethyl.
Under standard nomenclature used throughout this disclosure, the terminal portion of the designated side chain is described first, followed by the adjacent functionality toward the point of attachment. Thus, for example, a xe2x80x9cphenyl(alkyl)amido(alkyl)xe2x80x9d substituent refers to a group of the formula 
Where the compounds according to this invention have at least one chiral center, they may accordingly exist as enantiomers. Where the compounds possess two or more chiral centers, they may additionally exist as diastereomers. It is to be understood that all such isomers and mixtures thereof are encompassed within the scope of the present invention. Furthermore, some of the crystalline forms for the compounds may exist as polymorphs and as such are intended to be included in the present invention. In addition, some of the compounds may form solvates with water (i.e., hydrates) or common organic solvents, and such solvates are also intended to be encompassed within the scope of this invention.
As used herein, the term xe2x80x9ccis racematexe2x80x9d indicates a mixture of four possible diastereomers, more particularly, two cis diastereomers and two trans diastereomers, with the two cis diastereomers present in a amount equal to greater than about 75%, preferably in an amount greater than about 90%, more preferably in an amount greater than about 95%.
When a particular group is xe2x80x9csubstitutedxe2x80x9d (e.g., aryl, heteroaryl, heterocyclyl), that group may have one or more substituents, preferably from one to five substituents, more preferably from one to three substituents, most preferably from one to two substituents, independently selected from the list of substituents. Where the group has a plurality of moieties, such as xe2x80x9calkylaminoxe2x80x9d or xe2x80x9cheterocyclyl-alkylxe2x80x9d the substitution may be on any or all of the moieties independently, e.g. in the case of xe2x80x9calkylaminoxe2x80x9d the substitution may be on the alkyl or amino moiety, or both.
It is intended that the definition of any substituent or variable at a particular location in a molecule be independent of its definitions elsewhere in that molecule. It is understood that substituents and substitution patterns on the compounds of this invention can be selected by one of ordinary skill in the art to provide compounds that are chemically stable and that can be readily synthesized by techniques known in the art as well as those methods set forth herein.
Suitable protecting groups as referred to within this specification include the standard hydroxy and amino protecting groups, as applicable. The terms xe2x80x9chydroxy protecting groupxe2x80x9d and xe2x80x9camino protecting groupxe2x80x9d as used herein mean any of the known protecting groups used in the art of organic synthesis, for example as described in Protective Groups in Organic Synthesis, 2nd Ed., T. W. Greene and P. G. M. Wuts, John Wiley and Sons, New York, 1991, hereby incorporated by reference.
Examples of hydroxy-protecting groups P, include, but are not limited to, methyl, benzyl, tetrahydropyranyl, tri(C1-C6)alkylsilyl such as t-butyldimethylsilyl, t-butyl, 2-methoxyethoxymethyl (MEM), 4-dimethylcarbamoylbenzyl and O-phenoxyacetyl ethers. The hydroxy-protecting group selected is preferably one that is easily removable in the reaction process.
Examples of suitable amino protecting groups include, but are not limited to, acetyl (Ac), benzoyl (Bz), trifluoroacetyl (Tfa), toluenesulfonyl (Tos), benzyl (Bn), triphenylmethyl (Trt), o-nitrophenyl-sulfenyl (Nps), benzyloxycarbonyl (Cbz or Z), t-butoxycarbonyl (Boc), allyloxycarbonyl (alloc), 9-fluorenylmethyloxycarbonyl (Fmoc), 2-bromo-benzyloxycarbonyl (2-Br-Z), 2-chloro-benzyloxycarbonyl (2-Cl-Z), t-butyl-dimethylsilyloxycarbonyl, [2-(3,5-dimethoxyphenyl)-propyl-2-oxycarbonyl] (Ddz), 2,2,2-trichloroethyloxycarbonyl (Troc), biphenylylisopropyloxycarbonyl (Bpoc), and o-nitrobenzyloxycarbonyl.
Throughout this specification, certain abbreviations are employed having the following meanings, unless specifically indicated otherwise.
The synthesis of substituted N-benzyl-m-anisidines, compounds of formula (II), intermediates used in the synthetic route for select compounds of the invention, are known in the art. 
Routes for synthesis of substituted N-benzyl-m-anisidines include alkylation (Hoerlein; Chem. Ber.; 87; 1954; 463, 467, 468), reductive amination (Nussbaumer, P.; et. al.; J Med Chem.; 37; 24; 1994; 4079-4084) and reduction of the corresponding N-benzoyl-m-anisidine (Pratt; McGovern; J. Org. Chem.; 29; 1964; 1540, 1542). Additionally, N-benzyl-N-phenyl-malonamic acid methyl ester, a compound of formula (III) below, is a known compound, a variant of one of the intermediates elucidated in the synthesis that follows (Wee, A.; Tetrahedron, 50; 3; 1994; 609-626). 
Routes to the synthesis of 4-phenyl-1,2,3,4-tetrahydroisoquinolines are also known in the literature (Maryanoff, B., et. al., J. Org. Chem., 46, 1981, 355-360; Schwan, T. et. al., J. Heterocycl. Chem., 1974, 11, 807; and references therein).
Schemes 1-8 below depict synthesis routes for producing compounds of the formula (I).
Compounds of formula (I) wherein X2 and X3 are each carbonyl, X1 and X4 are each absent and R3 is xe2x80x94CH2xe2x80x94R6, may be produced according to the process outlined in Scheme 1. The process of Scheme 1 is particularly preferred for preparation of compounds of formula (I) wherein A is incorporated into the molecule via reaction with a suitably selected unsymmetrically substituted anhydride; wherein A is a substituted alkyl; and wherein it is desired to have the substituent closer to the R1X1R2N portion of the compound of formula (I). 
More specifically, a protected aniline derivative of formula (IV), wherein Pt represents a protecting group, a known compound or compound prepared by known methods, is reacted with a suitably substituted aldehyde of the formula (V), wherein R3A is selected from hydrogen, aryl, heterocyclyl, aralkyl, diarylalkyl, heterocyclo-alkyl, tri-halomethyl, alkylamino, dialkylamino, alkylaminoalkyl, arylamino, diarylamino or lower alkyl; in the presence of a reducing agent such as sodium cyanoborohydride, sodium triacetoxyborohydride, and the like, under dehydrating conditions, for example, in an acid alcohol solution such as acidic methanol or in a solution of titanium tetraisopropoxide in DCM, to produce the corresponding secondary aniline derivative of formula (VI).
The secondary aniline derivative of formula (VI) is coupled with a suitably selected, protected dicarboxylic acid of formula (VII), wherein Pt"" is a protecting group or with an anhydride of the desired substituent A, to produce the corresponding acid-amide of formula (VII).
When the secondary aniline derivative of formula (VI) is coupled with a cyclic anhydride of the desired substituent A, such as glutaric anhydride and the like, the anhydride ring is subjected to ring opening, preferably at a temperature between about room temperature and about 110xc2x0 C., in an organic solvent such as chloroform, toluene, and the like.
When the secondary aniline derivative of formula (VI) is coupled with a protected dicarboxylic acid of formula (VII), the protecting group is then removed by hydrolysis, using an inorganic base such as lithium hydroxide, sodium hydroxide, potassium hydroxide, and the like, in an alcohol or in an organic solvent/water mixture such as methanol, ethanol, THF/water, preferably lithium hydroxide in THF/water.
The acid-amide compound of formula (VII) is activated using a known coupling agent, such as EDCl and the like, and coupled with a suitably substituted amine of formula (IX), in an organic base such as TEA, DIEA, and the like, in the presence of an organic solvent such as THF, DMF, DCM and the like, to produce the corresponding diamide of formula (X).
Alternatively, the acid-amine compound of formula (VIII) may be converted to the corresponding acid chloride with a reagent such thionyl chloride, oxalyl chloride, and the like, and then coupled to the substituted amine of formula (IX) to produce the diamide of formula (X).
The compound of formula (X) is deprotected by known methods [for example, when the protecting group is methyl ether, the methyl group is removed with boron tribromide in dichloromethane at xe2x88x9278xc2x0 C.; when the protecting group is t-butyldimethylsilylether, the silyl group is removed with tetrabutylammonium fluoride in THF] to produce the corresponding compound of formula (XI).
The compound of formula (XI) is reacted with a suitably substituted compound of formula (XII), wherein W represents a leaving group such as halogen, OMS, OTos, and the like, in the presence of a base such as sodium hydride, potassium carbonate, and the like, in an organic solvent such as DMF, THF, and the like, to produce the corresponding compound of formula (Ia). Alternatively, when W is OH, the compound of formula (XI) may be reacted directly, under Mitsunobu conditions, to a suitably substituted compound of formula (XII).
Compounds of formula (I) wherein X2 and X3 are each carbonyl, X1 and X4 are each absent and R3 is xe2x80x94CH2xe2x80x94R6 may alternatively be prepared according to the process outlined in Scheme 2.
Accordingly, a suitably substituted nitrobenzene of formula (XIII), a compound prepared by known methods, is reacted with a suitably substituted compound of formula (XII), wherein W represents a leaving group such as halogen, OMS, OTos, and the like, in the presence of a base such as sodium hydride, triethylamine, and the like, in an organic solvent such as DMF, THF, and the like, to produce the corresponding compound of formula (XIV).
The nitro group on the compound of formula (XIV) is reduced by known methods, for example by hydrogenation over palladium on carbon in ethyl acetate, to produce the corresponding compound of formula (XV).
The compound of formula (XV) is reacted with a suitably substituted aldehyde of formula (V), wherein R3A is as previously defined, in the presence of a reducing agent such as sodium cyanoborohydride, sodium triacetoxyborohydride, and the like, under dehydrating conditions, for example, in an acid alcohol solution such as acidic methanol or in a solution of titanium tetraisopropoxide in DCM, to produce the corresponding compound of formula (XVI).
The compound of formula (XVI) is reacted with a suitably selected anhydride of the desired A substituent, optionally in an organic solvent such as THF, DMF, DCM, and the like, to produce the corresponding compound of formula (XVII). When reacting with a cyclic anhydride of the desired substituent A, such as glutaric anhydride and the like, the anhydride ring is subjected to ring opening, preferably at a temperature between about room temperature and about 110xc2x0 C., in an organic solvent such as chloroform, toluene, and the like.
The compound of formula (XVII) is coupled with a suitably substituted amine of formula (IX), in the presence of a coupling agent, such as PyBOP, and the like, in an organic solvent such as THF, DMF, DCM, and the like, to produce the corresponding compound of formula (Ib).
Compounds of formula (I) wherein X2 and X3 are each carbonyl, X1 and X4 are each absent and R3 is xe2x80x94CH2xe2x80x94R6, may alternatively be prepared according to the process outlined in Scheme 3. This process is particularly preferred for preparation of compounds of formula (I) wherein A is incorporated into the molecule via reaction with a suitably selected, unsymmetrically substituted anhydride; wherein A is a substituted alkyl; and wherein it is desired to have the substituent distal to the R1X1R2N portion of the compound of formula (I). 
More specifically, a suitably substituted amine of formula (IX) is reacted with a suitably selected anhydride of the desired A substituent, in an organic solvent such as THF, DMF, DCM, and the like, to produce the corresponding compound of formula (XVIII). When the compound of formula (IX) is coupled with a cyclic anhydride of the desired A substituent, such as glutaric anhydride and the like, the anhydride ring is subjected to ring opening, preferably at a temperature between about room temperature and about 110xc2x0 C., in an organic solvent such as chloroform, toluene, and the like.
The compound of formula (XVIII) is coupled with a suitably substituted compound of formula (XVI), prepared as in Scheme 2 above, in an organic solvent such as THF, DMF, DCM and the like, after conversion of the compound of formula (XVIII) to the corresponding acid chloride using a reagent such as thionyl chloride, oxalyl chloride, and the like, to produce the corresponding compound of formula (Ib).
Alternatively, the compound of formula (XVIII) may be coupled directly with a suitably substituted compound of formula (XVI), optionally in the presence of a coupling agent such as PyBrop, and the like, in an organic solvent such as THF, DMF, DCM, and the like.
Compounds of formula (I) wherein X1 and X3 are each absent, X2 is carbonyl, and X4 is carbonyl or sulfonyl, may be prepared according to the process outlined in Scheme 4.
More specifically, an anhydride of the desired substituent A is reacted with a suitably substituted compound of formula (XIV), prepared as outlined in scheme 2, in an organic solvent such as THF, DMF, DCM and the like, to produce the corresponding compound of formula (XIX).
The compound of formula (XIX) is coupled with a suitably substituted amine of formula (IX), in the presence of a coupling agent, such as PyBOP, and the like, in an organic solvent such as THF, DMF, DCM and the like, to produce the corresponding compound of formula (XX).
The compound of formula (XX) is selectively reduced, by known methods, for example, by reacting with sodium cyanoborohydride in AcOH (Tetrahedron Letters, 10, 763-66, 1976), to produce the corresponding compound of formula (XXI).
The compound of formula (XXI) is reacted with an appropriately selected and suitably substituted isocyanate of formula (XXII), wherein R3A is a previously defined, or a sulfonyl chloride of formula (XXIII) or a carbonyl chloride of formula (XXIV), in an organic solvent such as THF, DMF, DCM and the like, to produce the corresponding compound of formula (Ic).
Compounds of formula (I) wherein X1 and X4 are each carbonyl or sulfonyl and X2 and X3 are each absent, may be prepared according to the process outlined in Scheme 5. This process is particularly preferred for the preparation of compounds of formula (I) wherein A is -cyclohexyl-methyl-, -cyclopentyl-methyl and -cyclopentenyl-methyl-. 
Accordingly, a trityl-protected compound of formula (XXV), wherein A1 is cycloalkyl, cycloalkenyl, alkyl-cycloalkyl, aryl or alkyl-aryl, a known compound or compound prepared by known methods, [for example by the method disclosed in K. Barlos, D. Theodoropoulos, and D. Papaioannou in J. Org. Chem. 1982, 47, 1324-1326], is coupled to a suitably substituted compound of formula (XIV), prepared according to Scheme 2 above, using a coupling agent such as PyBOP, and the like, to produce the corresponding compound of formula (XXVI).
The compound of formula (XXVI) is subjected to reduction of the carbonyl group using known reducing agents, for example borane dimethylsulfide at reflux, lithium aluminum hydride in THF, and the like, to produce the corresponding compound of formula (XXVII).
The compound of formula (XXVII) is reacted with an appropriately selected and suitably substituted isocyanate of formula (XXII), wherein R3A is as previously defined, sulfonyl chloride of formula (XXIII) or carbonyl chloride of formula (XXIV), in an organic solvent such as DCM, toluene, chloroform, and the like, to produce the corresponding compound of formula (XXVIII).
The compound of formula (XXVIII) is deprotected by removal of the trityl protecting group, using a solution of trifluoroacetic acid in dichloromethane, to produce the corresponding compound of formula (XXIX).
The compound of formula (XXIX) is reacted with a suitably substituted aldehyde of formula (XXX), wherein R1A is selected from the group consisting of hydrogen, aryl, aralkyl, heterocyclyl, diarylalkyl, heterocyclyl-alkyl, and lower alkyl; wherein the alkyl, aryl, heterocyclyl or amino group may be substituted with one or more substituents independently selected from halogen, hydroxy, nitro, carboxy, cyano, amino, dialkylamino, lower alkoxy, lower alkyl, tri-halomethyl, alkylamino, carboxy or alkoxycarbonyl; by known methods, [for example by reductive amination or by the method of R. Mattson, et. al., in J. Org. Chem. 1990, 55, 2552-2554 using stepwise addition of titanium tetraisopropoxide neat or in a dichloromethane, followed by addition of methanol and sodiumcyanoborohydride], to produce the corresponding compound of formula (XXXI).
The compound of formula (XXXI) is reacted with an appropriately selected and suitably substituted isocyanate of formula (XXXII), wherein R2A is selected from aryl, aralkyl, heterocyclyl, heterocyclyl-alkyl, diarylalkyl, tri-halomethyl, arylamino or lower alkyl, or a sulfonyl chloride of formula (XXXIII) or a carbonyl chloride of formula (XXXIV), or an anhydride of formula (XXXXVII) in an organic solvent such as DCM, toluene, and the like, to produce the corresponding compound of formula (Id). When the compound of formula (XXXI) is reacted with a sulfonyl chloride of formula (XXXIII) or a carbonyl chloride of formula (XXXIV), the reaction is carried out with further addition of an organic base such as TEA, DIPEA, and the like.
Compounds of formula (I) wherein A is a substituted alkyl may alternatively be prepared according to the process outlined in Scheme 6. 
More specifically, a suitably substituted compound of formula (XVI), prepared as described in Scheme 2 above, is coupled with an appropriately selected, Fmoc protected compound of formula (XXXV), in an organic solvent such as DCM, DMF, and the like, to produce the corresponding compound of formula (XXXVI).
The compound of formula (XXXVI) is deprotected by removal of the Fmoc protecting group by known methods [for example by treating with piperidine in DMF], to produce the corresponding compound of formula (XXXVII).
The compound of formula (XXXVII) is reacted with a suitably substituted aldehyde of formula (XXX), wherein R1A is as previously defined, in the presence of a reducing agent such as sodium cyanoborohydride, and the like, under dehydrating conditions, for example in an acid alcohol solution such as acidic methanol or in a solution of titanium tetraisopropoxide in DCM, followed by addition of methanol and sodium cyanoborohydride, to produce the corresponding compound of formula (XXXVIII).
The compound of formula (XXXVIII) is coupled with an appropriately selected and suitably substituted isocyanate of formula (XXXII), wherein R2A is as previously defined, sulfonyl chloride of formula (XXXIII) or carbonyl chloride of formula (XXXIV), in an organic solvent such as DCM, and the like, in the presence of an organic base such as TEA, DIEA, and the like, to produce the corresponding compound of formula (Ie).
Optionally, the compound of formula (XXXVIII) may be further reacted with a second equivalent of the compound of formula (XXX) to yield a derivative of the compound of formula (XXXVIII), wherein the leftmost amine nitrogen is disubstituted with the xe2x80x94CH2xe2x80x94R1A group, wherein R1A is as previously defined.
Compounds of formula (I), particularly those wherein X1 and X3 are each absent, X2 is carbonyl and X4 is carbonyl or sulfonyl may be prepared according to the process outlined in Scheme 7. This process is particularly preferred for preparation of compounds of formula (I) wherein A is contains a non-hydrogen substituent alpha to the right-hand most amine nitrogen. 
Accordingly, a suitably substituted compound of formula (XV), prepared as in Scheme 2 above, is alkylated with an appropriately selected compound of formula (XXXIX), ins an organic solvent such as DCM, chloroform, and the like, to produce the corresponding compound of formula (XXXX).
The compound of formula (XXXX) is coupled with an appropriately selected and suitably substituted isocyanate of formula (XXII), wherein R3A is as previously defined, sulfonyl chloride of formula (XXIII) or carbonyl chloride of formula (XXIV), in an organic solvent such as DCM, and the like, to produce the corresponding compound of formula (XXXXI). When the compound of formula (XXXX) is reacted with a sulfonyl chloride of formula (XXXIII) or a carbonyl chloride of formula (XXXIV), the reaction is run in the presence of an organic base such as TEA, DIEA, and the like.
The compound of formula (XXXXI) is subjected to hydrolysis of the methyl ester, in the presence of an inorganic base such as sodium hydroxide, and the like, to produce the corresponding compound of formula (XXXXII).
The compound of formula (XXXXII) is coupled with a suitably substituted amine of formula (IX), in the presence of a coupling agent such as PyBOP, and the like, in an organic solvent such as DCM, and the like, to produce the corresponding compound of formula (If).
Compounds of formula (I), particularly those wherein X1 and X4 are each carbonyl or sulfonyl and X2 and X3 are each absent may be prepared according to the process outlined in Scheme 8
Accordingly, wherein A1 is an oxo and cyano substituted cycloalkyl, an oxo and cyano substituted cycloalkenyl, an oxo and cyano substituted cycloalkyl-alkyl, an oxo-alkyl and cyano substituted aryl or an oxo-alkyl and cyano-alkyl substituted aryl-alkyl, a known compound or compound prepared by known methods, is reacted with a compound of formula (XV), prepared as outlined in Scheme 2, in the presence of a reducing agent such as sodium cyanoborohydride, and the like, under dehydrating conditions, for example in an acid alcohol solution such as acidic methanol, to produce the corresponding compound of formula (XXXXIII).
The compound of formula (XXXXIII) is reacted with an appropriately selected and suitably substituted isocyanate of formula (XXII), wherein R3A is as previously defined, sulfonyl chloride of formula (XXIII) or carbonyl chloride of formula (XXIV), in an organic solvent such as DCM, and the like, to produce the corresponding compound of formula (XXXXIV). When the compound of formula (XXXXIII) is reacted with a sulfonyl chloride of formula (XXIII) or a carbonyl chloride of formula (XXIV), the reaction is run in the presence of an organic base such as TEA, DIEA, and the like.
The cyano functional group on the compound of formula (XXXXIV) is reduced by known methods, for example by treatment with lithium aluminum hydride, in an organic solvent such as THF, and the like, to produce the corresponding compound of formula (XXXXV).
The compound of formula (XXXXV) is reacted with a suitably substituted aldehyde of formula (XXX), wherein R1A is as previously defined, in the presence of a reducing agent such as sodium cyanoborohydride, and the like, under dehydrating conditions, for example in an acid alcohol solution such as acidic methanol or in a solution of titanium tetraisopropoxide in DCM, followed by addition of methanol and sodium cyanoborohydride, to produce the corresponding compound of formula (XXXXVI).
The compound of formula (XXXXVI) is reacted with an appropriately selected and suitably substituted isocyanate of formula (XXXII), wherein R2A is as previously defined, sulfonyl chloride of formula (XXXIII), or carbonyl chloride of formula (XXXIV), in an organic solvent such as DCM, and the like, to produce the corresponding compound of formula (Ig). When the compound of formula (XXXXVI) is reacted with a sulfonyl chloride of formula (XXXIII) or a carbonyl chloride of formula (XXXIV), the reaction is run in the presence of an organic base such as TEA, DIEA, and the like.
Compounds of formula (I) wherein R1, X1 and R2 are taken together (with the amine nitrogen) to form an oxo substituted heterocyclyl group, may be prepared according to the process outlined in Scheme 9.
More particularly, the compound of formula (XXIX), prepared as in Scheme 5, is reacted with a suitably substituted symmetric or asymmetric anhydride, a compound of formula (XXXXVII), preferably a symmetric anhydride, in an organic solvent such as toluene, DCM, and the like, to yield the corresponding compound of formula (XXXXVIII).
The compound of formula (XXXXVIII) is heated at an elevated temperature in the range of about 40-180xc2x0 C., or treated with addition of an anhydride such as acetic anhydride, trifluoroacetic anhydride, and the like, in an organic solvent such as methylene chloride, toluene, 1,2-dichlorobenzene, and the like, to yield the corresponding compound of formula (Ih), wherein 
represents the group wherein R1, R2 and X1 are taken together (with the amine nitrogen) to form a cyclic oxo substituted heterocyclyl.
Wherein the compound of formula (XXXXVII) is an asymmetric anhydride, (a compound of the formula R2xe2x80x2xe2x80x94C(O)xe2x80x94C(O)xe2x80x94R2xe2x80x3, wherein R2xe2x80x2 and R2xe2x80x3 are different), the R2 group which is coupled onto the compound of formula (XXIX) may be readily determined by one skilled in the art, based on the relative reactivities of the carbonyl groups adjacent to the R2xe2x80x2 and R2xe2x80x3 groups.
It is generally preferred that the respective product of each process step be separated from other components of the reaction mixture and subjected to purification before its use as a starting material in a subsequent step. Separation techniques typically include evaporation, extraction, precipitation and filtration. Purification techniques typically include column chromatography (Still, W. C. et. al., J. Org. Chem. 1978, 43, 2921), thin-layer chromatography, HPLC, acid-base extraction, crystallization and distillation.
Where the compounds according to this invention have at least one chiral center, they may accordingly exist as enantiomers. Where the compounds possess two or more chiral centers, they may additionally exist as diastereomers. It is to be understood that all such isomers and mixtures thereof are encompassed within the scope of the present invention.
Where the processes for the preparation of the compounds according to the invention give rise to mixture of stereoisomers, these isomers may be separated by conventional techniques such as preparative chromatography. The compounds may be prepared in racemic form, or individual enantiomers may be prepared either by enantiospecific synthesis or by resolution. The compounds may, for example, be resolved into their component enantiomers by standard techniques, such as the formation of diastereomeric pairs by salt formation with an optically active acid, such as (xe2x88x92)-di-p-toluoyl-d-tartaric acid and/or (+)-di-p-toluoyl-n-tartaric acid followed by fractional crystallization and regeneration of the free base. The compounds may also be resolved by formation of diastereomeric esters or amides, followed by chromatographic separation and removal of the chiral auxiliary. Alternatively, the compounds may be resolved by enzymatic resolution or by using a chiral HPLC column.
To prepare the pharmaceutical compositions of this invention, one or more compounds or salts thereof, as the active ingredient, is intimately admixed with a pharmaceutical carrier according to conventional pharmaceutical compounding techniques, which carrier may take a wide variety of forms depending on the form of preparation desired for administration, e.g., oral or parenteral. In preparing the compositions in oral dosage form, any of the usual pharmaceutical media may be employed. Thus for liquid oral preparations, such as for example, suspensions, elixirs and solutions, suitable carriers and additives include water, glycols, oils, alcohols, flavoring agents, preservatives, coloring agents and the like; for solid oral preparations such as, for example, powders, capsules and tablets, suitable carriers and additives include starches, sugars, diluents, granulating agents, lubricants, binders, disintegrating agents and the like. Because of their ease in administration, tablets and capsules represent the most advantageous oral dosage form, in which case solid pharmaceutical carriers are obviously employed. If desired, tablets may be sugar coated or enteric coated by standard techniques. For parenterals, the carrier will usually comprise sterile water, though other ingredients, for example, for purposes such as aiding solubility or for preservation, may be included. Injectable suspensions may also be prepared, in which case appropriate liquid carriers, suspending agents and the like may be employed. The pharmaceutical compositions herein will preferably contain per dosage unit, e.g., tablet, capsule, powder, injection, teaspoonful and the like, from about 5 to about 500 mg of the active ingredient, although other unit dosages may be employed.
In therapeutic use for treating disorders of the gastrointestinal system in mammals, the compounds of this invention may be administered in an amount of from about 0.5 to 100 mg/kg 1-2 times per day orally. In addition the compounds may be administered via injection at 0.1-10 mg/kg per day. Determination of optimum dosages for a particular situation is within the capabilities of formulators.
In order to illustrate the invention, the following examples are included. These examples do not limit the invention. They are meant to illustrate and suggest a method of practicing the invention. Although there are other methods of practicing this invention, those methods are deemed to be within the scope of this invention.